Providers of communication services, such as telecommunication service providers, have detailed records of their subscribers' wireless activities. This information includes location—when a subscriber uses his or her cell phone and often a billing address for an account. Billing addresses can provide insight into where subscribers live, helping service providers better target and develop services and advertise those services. However, this information is not always an accurate representation of where the device is most often used and is not always available (e.g., for prepaid subscribers).
While lacking direct information specifying meaningful locations for subscribers, such as home or work locations, these service providers may have other information available to them that can be used to derive such locations. For example, when subscribers initiate communications or connect to a network of the service provider, both the cell tower location and a time may be captured.